android将老项目改为按屏幕大小自适应，只需2步

先看效果图

老项目​​​​

自适应后

目标：老项目是320*480，改为按屏幕大小自适应。

1.主要是图片和坐标，我都放在一个类里了，改下包名，直接加入项目。

package wyf.ytl;

import java.io.IOException;

import android.app.Activity;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Matrix;
import android.util.DisplayMetrics;

public class ZoomImg {
	public final static int widthOld = 320; // 原设计屏幕宽度
	public final static int heithtOld = 480;
	public static float widthScale = 1; // 原转为新 比例系数
	public static float heightScale = 1; //原设计屏幕高度
	public static float widthScaleTouch = 1; // 新转为原 比例系数 反向，比如触控坐标，原值不动，只缩放xy.
	public static float heightScaleTouch = 1;
	/**根据原设计屏幕 缩放图片 使能自适应
	 * 
	 * @param bm 原图片
	 * @param activity 所在界面 。如果当前就是在Activity直接用this
	 * @return 自适应后的图片
	 */
	public static Bitmap zoomImgAuto(Bitmap bm, Activity activity) {
		getScreen(activity);// 根据屏幕大小计算出比例系数
		if (null != bm) {
			return zoomImg(bm, (int) (bm.getWidth() * widthScale),
					(int) (bm.getHeight() * heightScale));
		}
		return null;
	}

	
	
	
	/**根据屏幕大小计算出比例系数
	 * 
	 * @param activity 所在界面
	 */
	public static void getScreen(Activity activity)
	{
		DisplayMetrics outMetrics = new DisplayMetrics();
		activity.getWindowManager().getDefaultDisplay().getMetrics(outMetrics);
		int widthPixels = outMetrics.widthPixels;
		int heightPixels = outMetrics.heightPixels;
		// Log.i(TAG, "widthPixels = " + widthPixels + ",heightPixels = " +
		// heightPixels);
		widthScale = (float) widthPixels / (float) widthOld;
		heightScale = (float) heightPixels / (float) heithtOld;

		widthScaleTouch = (float) widthOld / (float) widthPixels;
		heightScaleTouch = (float) heithtOld / (float) heightPixels;
	}
	// 缩放图片
	public static Bitmap zoomImg(String img, int newWidth, int newHeight) {
		// 图片源
		Bitmap bm = BitmapFactory.decodeFile(img);
		if (null != bm) {
			return zoomImg(bm, newWidth, newHeight);
		}
		return null;
	}

	public static Bitmap zoomImg(Context context, String img, int newWidth,
			int newHeight) {
		// 图片源
		try {
			Bitmap bm = BitmapFactory.decodeStream(context.getAssets()
					.open(img));
			if (null != bm) {
				return zoomImg(bm, newWidth, newHeight);
			}
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		return null;
	}

	// 缩放图片
	public static Bitmap zoomImg(Bitmap bm, int newWidth, int newHeight) {
		// 获得图片的宽高
		int width = bm.getWidth();
		int height = bm.getHeight();
		// 计算缩放比例
		float scaleWidth = ((float) newWidth) / width;
		float scaleHeight = ((float) newHeight) / height;
		// 取得想要缩放的matrix参数
		Matrix matrix = new Matrix();
		matrix.postScale(scaleWidth, scaleHeight);
		// 得到新的图片
		Bitmap newbm = Bitmap.createBitmap(bm, 0, 0, width, height, matrix,
				true);
		return newbm;
	}
}

2.将所有坐标和图片都这样处理就可以了。 

为了能一键替换，继续封装

package wyf.ytl;

import java.io.IOException;

import android.app.Activity;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Matrix;
import android.graphics.Paint;
import android.util.DisplayMetrics;

public class ZoomImg extends Canvas {
	public final static int widthOld = 320; // 原设计屏幕宽度
	public final static int heithtOld = 480;
	public static float widthScale = 1; // 原转为新 比例系数
	public static float heightScale = 1; //原设计屏幕高度
	public static float widthScaleTouch = 1; // 新转为原 比例系数 反向，比如触控坐标，原值不动，只缩放xy.
	public static float heightScaleTouch = 1;
	public static void drawText(Canvas canvas,Activity activity,String text, float x, float y, Paint paint)
	{
		canvas.drawText(text, x*widthScale, y*heightScale, paint);//绘制图片
	}
	public static void drawBitmap(Canvas canvas,Activity activity,Bitmap bitmap, float left, float top, Paint paint)
	{
		canvas.drawBitmap(zoomImgAuto(bitmap,activity), left*widthScale, top*heightScale, null);//绘制图片
	}
	/**根据原设计屏幕 缩放图片 使能自适应
	 * 
	 * @param bm 原图片
	 * @param activity 所在界面 。如果当前就是在Activity直接用this
	 * @return 自适应后的图片
	 */
	public static Bitmap zoomImgAuto(Bitmap bm, Activity activity) {
		getScreen(activity);// 根据屏幕大小计算出比例系数
		if (null != bm) {
			return zoomImg(bm, (int) (bm.getWidth() * widthScale),
					(int) (bm.getHeight() * heightScale));
		}
		return null;
	}

	
	
	
	/**根据屏幕大小计算出比例系数
	 * 
	 * @param activity 所在界面
	 */
	public static void getScreen(Activity activity)
	{
		DisplayMetrics outMetrics = new DisplayMetrics();
		activity.getWindowManager().getDefaultDisplay().getMetrics(outMetrics);
		int widthPixels = outMetrics.widthPixels;
		int heightPixels = outMetrics.heightPixels;
		// Log.i(TAG, "widthPixels = " + widthPixels + ",heightPixels = " +
		// heightPixels);
		widthScale = (float) widthPixels / (float) widthOld;
		heightScale = (float) heightPixels / (float) heithtOld;

		widthScaleTouch = (float) widthOld / (float) widthPixels;
		heightScaleTouch = (float) heithtOld / (float) heightPixels;
	}
	// 缩放图片
	public static Bitmap zoomImg(String img, int newWidth, int newHeight) {
		// 图片源
		Bitmap bm = BitmapFactory.decodeFile(img);
		if (null != bm) {
			return zoomImg(bm, newWidth, newHeight);
		}
		return null;
	}

	public static Bitmap zoomImg(Context context, String img, int newWidth,
			int newHeight) {
		// 图片源
		try {
			Bitmap bm = BitmapFactory.decodeStream(context.getAssets()
					.open(img));
			if (null != bm) {
				return zoomImg(bm, newWidth, newHeight);
			}
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		return null;
	}

	// 缩放图片
	public static Bitmap zoomImg(Bitmap bm, int newWidth, int newHeight) {
		// 获得图片的宽高
		int width = bm.getWidth();
		int height = bm.getHeight();
		// 计算缩放比例
		float scaleWidth = ((float) newWidth) / width;
		float scaleHeight = ((float) newHeight) / height;
		// 取得想要缩放的matrix参数
		Matrix matrix = new Matrix();
		matrix.postScale(scaleWidth, scaleHeight);
		// 得到新的图片
		Bitmap newbm = Bitmap.createBitmap(bm, 0, 0, width, height, matrix,
				true);
		return newbm;
	}
}